Endocardial extent of infarction. Late gadolinium enhanced (LGE) CMR showing short-axis slices covering base (top left) to apex (bottom right) in a patient with an occlusion of the left anterior descending coronary artery. The endocardial borders are traced in red and the epicardial borders are traced in green. The infarct is shown as an LGE area within the myocardial borders and is delineated in yellow. The circumferential endocardial extent of LGE is marked by the solid arrow (α) and the remote myocardium is marked by the dashed arrow (β). The endocardial extent of MI was defined as the sum of the LGE circumferential endocardial extent in each short-axis slice (∑α), divided by the total endocardial extent (∑ [α + β]) of the LV. In this patient, the MaR by T2-weighted imaging and LGE endocardial extent was 37% and 32%, respectively. The corresponding infarct size was 32%, resulting in a myocardial salvage of 13% and 1% when measured with T2-weighted imaging and LGE endocardial extent, respectively.